// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_RENDERER_SPEECH_RECOGNITION_DISPATCHER_H_
#define CONTENT_RENDERER_SPEECH_RECOGNITION_DISPATCHER_H_

#include <map>
#include <memory>

#include "base/macros.h"
#include "base/memory/shared_memory.h"
#include "base/sync_socket.h"
#include "content/public/common/speech_recognition_result.h"
#include "content/public/renderer/render_view_observer.h"
#include "media/media_features.h"
#include "third_party/WebKit/public/platform/WebMediaStreamTrack.h"
#include "third_party/WebKit/public/platform/WebVector.h"
#include "third_party/WebKit/public/web/WebSpeechRecognitionHandle.h"
#include "third_party/WebKit/public/web/WebSpeechRecognizer.h"

namespace media {
class AudioParameters;
}

namespace content {
class RenderViewImpl;
#if BUILDFLAG(ENABLE_WEBRTC)
class SpeechRecognitionAudioSink;
#endif
struct SpeechRecognitionError;

// SpeechRecognitionDispatcher is a delegate for methods used by WebKit for
// scripted JS speech APIs. It's the complement of
// SpeechRecognitionDispatcherHost (owned by RenderViewHost).
class SpeechRecognitionDispatcher : public RenderViewObserver,
                                    public blink::WebSpeechRecognizer {
public:
    explicit SpeechRecognitionDispatcher(RenderViewImpl* render_view);
    ~SpeechRecognitionDispatcher() override;

    // Aborts all speech recognitions.
    void AbortAllRecognitions();

private:
    // RenderViewObserver implementation.
    bool OnMessageReceived(const IPC::Message& message) override;
    void OnDestruct() override;

    // blink::WebSpeechRecognizer implementation.
    void start(const blink::WebSpeechRecognitionHandle&,
        const blink::WebSpeechRecognitionParams&,
        blink::WebSpeechRecognizerClient*) override;
    void stop(const blink::WebSpeechRecognitionHandle&,
        blink::WebSpeechRecognizerClient*) override;
    void abort(const blink::WebSpeechRecognitionHandle&,
        blink::WebSpeechRecognizerClient*) override;

    void OnRecognitionStarted(int request_id);
    void OnAudioStarted(int request_id);
    void OnSoundStarted(int request_id);
    void OnSoundEnded(int request_id);
    void OnAudioEnded(int request_id);
    void OnErrorOccurred(int request_id, const SpeechRecognitionError& error);
    void OnRecognitionEnded(int request_id);
    void OnResultsRetrieved(int request_id,
        const SpeechRecognitionResults& result);
    void OnAudioReceiverReady(int session_id,
        const media::AudioParameters& params,
        const base::SharedMemoryHandle handle,
        const base::SyncSocket::TransitDescriptor socket);

    void ResetAudioSink();

    int GetOrCreateIDForHandle(const blink::WebSpeechRecognitionHandle& handle);
    bool HandleExists(const blink::WebSpeechRecognitionHandle& handle);
    const blink::WebSpeechRecognitionHandle& GetHandleFromID(int handle_id);

    // The WebKit client class that we use to send events back to the JS world.
    blink::WebSpeechRecognizerClient* recognizer_client_;

#if BUILDFLAG(ENABLE_WEBRTC)
    // Media stream audio track that the speech recognition connects to.
    // Accessed on the render thread.
    blink::WebMediaStreamTrack audio_track_;

    // Audio sink used to provide audio from the track.
    std::unique_ptr<SpeechRecognitionAudioSink> speech_audio_sink_;
#endif

    typedef std::map<int, blink::WebSpeechRecognitionHandle> HandleMap;
    HandleMap handle_map_;
    int next_id_;

    DISALLOW_COPY_AND_ASSIGN(SpeechRecognitionDispatcher);
};

} // namespace content

#endif // CONTENT_RENDERER_SPEECH_RECOGNITION_DISPATCHER_H_
